This Trump market rally is gathering steam — and it’s fueled by growing confidence among wealthy investors that the US now has the world’s greatest investment opportunities.

The Dow Jones industrial average is up 3.8 percent since the election.

A new report from Spectrem Group shows how this bullishness among individual US households, net worth exceeding $25 million, has soared in recent weeks, from just 16 percent in 2014 to 33 percent today.

Many, citing the US as having the world’s greatest investment potential, told pollsters of their plans to invest in US equity and short-term products in the next 12 months.

A separate Spectrem US investor confidence index, out next month, is expected to show further post-election signs of increasing confidence.

In contrast, Spectrem’s US millionaire confidence index fell to a four-month low in September as investors cited political uncertainty. “I am sure our new index will show a positive influence among the most affluent classes. We will just have to wait a couple more weeks,” Spectrem President George Walper Jr. told the The Post last week as the Dow hit new highs.

Some investors have already pulled the trigger. One affluent New York investor, Jonathan Braun, recently announced plans by his company, NextCoal International, to build a job-generating renewable fuels center with Japanese investors in rural upstate New York. The venture aims to manufacture bio-coal for export to Japanese power plants as well as bio-oil for domestic industry.

“There has been so much reporting on Japanese business leaders reacting negatively to the Trump election victory. My Japanese investor friends responded with enthusiasm to the news,” Braun told The Post, “because they believe, as I do, that our rural fuels manufacturing projects are in tune with Trump’s pledge to revive rural America.”

The center planned by NCI is expected to create 30 jobs and support another 300 jobs in forestry, engineering, construction, transportation and other fields. Meanwhile, Braun said his company is scouting out new offices in Manhattan — in space within walking distance of Trump Tower.